Why are two balls connected by a spring a good model for two atoms connected by a chemical bond?

• A. Because the spring always keeps the balls at a fixed distance, just as atoms in a chemical bond never change their separation.
• B. Because the balls and spring can rotate freely, just like atoms in a chemical bond.
• C. Because the spring represents the force that holds the atoms together and allows them to vibrate around an equilibrium position, similar to a chemical bond.
• D. Because the balls and spring model shows that atoms in a chemical bond are completely rigid and do not move.

Answer: (C)

Verified step by step guidance

1. Understand that in chemistry, atoms in a molecule are not fixed rigidly; they can vibrate around an equilibrium position due to the forces between them.
2. Recognize that a spring in physics is a common model for a restoring force that pulls objects back toward an equilibrium position when displaced, which is analogous to the chemical bond between atoms.
3. Note that the two balls represent atoms, and the spring represents the chemical bond that holds them together but also allows for vibrations (stretching and compressing) around a stable distance.
4. Realize that this model captures the dynamic nature of chemical bonds, where atoms oscillate rather than remain at a perfectly fixed distance, which is important for understanding molecular vibrations and energy.
5. Conclude that the spring-and-ball model is effective because it illustrates both the attractive force of the bond and the vibrational motion of atoms, unlike a rigid or fixed-distance model.